A millimeter wave band corresponding to 57 GHz to 66 GHz has been proposed as a scheme to ease a worldwide shortage of frequency resources. Also, since a wireless frequency signal of a millimeter wave band can be configured, a wireless communication system supporting a transmission rate of several gigabytes is recently gaining an attention.
A millimeter wave has unique characteristics, for example, a short wavelength, a high frequency, a wideband, a large amount of exchange with atmospheric components, and the like. The millimeter wave may have advantages in that a high data transmission rate can be obtained using an ultra wideband, that the millimeter wave is robust against peripheral interference due to a strong straightness, that the millimeter wave has an excellent security, that a frequency reuse is easy, and the like. A short wavelength of the millimeter wave may enable various devices to be miniaturized and be lightened.
In contrast, the millimeter wave may have disadvantages in that a propagation distance is short due to an absorption by oxygen molecules and due to a rainfall attenuation phenomenon that a line of sight needs to be secured due to a characteristic of straightness, and the like.
To complement the disadvantages of the millimeter wave, a directional antenna may be used. The directional antenna may concentrate power in a predetermined direction to enhance the antenna gain efficiency, thereby expanding a communication range.
Also, due to characteristics of the millimeter wave, the above wireless communication system may configure a network using distributed nodes that are positioned in a near distance.
A device to initiate a communication may verify neighbor devices in a current network, and may perform a discovery procedure of discovering a device to be communicated with.
When a communication device that is desired to be communicated with through the discovery procedure is determined, a process of selecting a channel suitable for communication from among channels allowed for the communication may be performed.